JP2002520433A - Microporous polyurethane elastomer foamed with permanent gas - Google Patents

Abstract

  (57) [Summary] Microporous polyurethane elastomers with apparently reduced urea linkages or virtually no urea linkages can be used to form isocyanate-reactive polyols and chain extenders and foams without the use of organic physical blowing agents It can be prepared by froth foaming a foamable mixture containing various isocyanate components. The isocyanate component is obtained by reacting a stoichiometric excess of a diisocyanate or polyisocyanate with a polyol component containing an ultra-low unsaturated polyol. Elastomers produced by floss foaming surprisingly exhibit significantly improved tear strength, compressive strain and other physical properties compared to all of the same density microporous elastomers foamed with water. Show.

Description

DETAILED DESCRIPTION OF THE INVENTION

TECHNICAL FIELD The present invention relates to a frothed microporous polyurethane elastomer. More particularly, the invention relates to microporous polyurethane elastomers prepared from low-unsaturation polyoxyalkylene polyethers and foamed with a permanent gas. Such microporous elastomers are well suited for use as sole components.

BACKGROUND OF THE INVENTION [0002] Microporous polyurethane elastomers are widely used, for example, as automotive components such as energy absorbing buffers, head supports and armrests, and especially as sole components. Prior to the Montreal Protocol, CFC-11 and CFC-22 were used to generate a number of very fine bubbles characteristic of microporous elastomers.
And volatile halocarbons such as methylene chloride could be used as the blowing agent. However, due to the severe limitations imposed on the use of halogenated hydrocarbons, and thus the increasing environmental concerns regarding the use of more environmentally friendly organic blowing agents, water-foamed microporous elastomers have Development has been forced.

In the case of water-blown polyurethane microporous elastomers, the water present in the formulation reacts with some of its isocyanate components to generate amines and carbon dioxide. Carbon dioxide serves as a blowing agent. However, the amine formed further reacts with the isocyanate to provide a urea linkage. The microporous elastomer produced in this way is not a polyurethane elastomer, but a polyurethane / urea elastomer containing urea bonds in fairly hard segments. Such elastomers are often harder and have less elasticity than their counterparts, which are all polyurethanes. More importantly, however, the tear strength of such elastomers is limited. Tear strength is particularly important in applications such as those in the footwear industry.

[0004] Flexible polyurethane foams have been air foamed for use in carpet backing and carpet backing applications. However, such foams are not microporous. Cell size is much smaller density of these foams (i.e., about 0.015 g / cm ³ ~ about 0.09 g / cm ³⁾ extremely large as demonstrated by its system, the applied load resistance Highly filled to increase. The required large cell size of such foams is coupled with the use of a doctor blade or the like to adjust the height of the foam, so that the collapse of the cells is to a large extent. The relatively low viscosity of the system for foaming such flexible foams contributes to both the large cell size as well as the tendency of these cells to collapse. Collapse cannot be tolerated in molded microporous elastomers, and the formulations used in foamed carpet backings are not suitable for microporous elastomers.

[0005] To provide microporous elastomers containing only urethane linkages or containing substantially all urethane linkages with only small amounts of urea linkages without the use of volatile organic blowing agents Is desirable. It is further desirable to provide polyurethane microporous elastomers that exhibit improved tear strength as compared to similar density polyurethane / urea microporous elastomers foamed with water.

SUMMARY OF THE INVENTION [0006] The present invention relates to floss foaming prepared by frothing the primary reactive polyurethane-forming component in the presence of a non-organic permanent gas and a foaming surfactant. And a flossed polyurethane / urea microporous elastomer having a much lower urea group content than the comparable polyurethane / urea microporous elastomer foamed with water. The A and B portions of the formulation can be foamed separately, and these two foams can be combined and processed as needed. The resulting polyurethane microporous elastomer and polyurethane / urea microporous elastomer are those in which a substantial portion of the polyoxypropylene polyol portion of the isocyanate-terminated prepolymer used to prepare the elastomer has a low unsaturated polyoxypropylene content. When it is a polyol, it has surprisingly improved tear strength.

The microporous polyurethane elastomers of the present invention generally comprise a feed stream of at least two reactive components (a resin feed stream containing a mixture of isocyanate-reactive polyols, and one or more foamable foams). Diisocyanate and / or polyisocyanate prepolymers, quasi-prepolymers or mixtures thereof, optionally with one or more diisocyanates or polyisocyanates, is supplied as isocyanate feed stream). It is prepared by foaming a microporous foamable polyurethane reactive component.

[0008] The resin part (Part B) contains a minimum amount of one or more isocyanate-reactive polyols and / or polymer polyols, and preferably contains a chain extender. Optional components include catalysts, crosslinkers, dyes, fillers, and other conventional additives. A foaming surfactant must also generally be present. Suitable isocyanate-reactive polyols have equivalent weights ranging from 1000 Da to 6,000 Da, preferably from 1500 Da to 5 Da.
A low-unsaturated polyoxypropylene polyol having a range of 2,000 Da, and more preferably a range of 1500 Da to 3,000 Da. The degree of unsaturation of these polyols must be less than 0.015 meq / g, preferably
It should be less than 10 meq / g, most preferably less than 0.007 meq / g. Molecular weights and equivalent weights herein in Da (Daltons) are number average equivalent weights and molecular weights, unless otherwise indicated. Suitable polyols include polyoxyalkylene polyols having a nominal functionality of about 2 to about 8. "Nominal functionality" means the theoretical functionality, i.e., the functionality of the initiator molecule used to prepare the polyol. Mixtures of polyoxyalkylene polyols are generally used, but preferably, such mixtures have an average functionality ranging from 2 to about 4 and an average equivalent weight greater than about 1000 Da.

[0009] The polyoxyalkylene polyol is preferably a polyoxypropylene homopolymer polyol, or a polyoxypropylene polyol containing up to about 30 weight percent oxyethylene moieties. In this case, such oxyethylene moieties are randomly dispersed within the polymer chain or are located at both ends of the polymer chain as polyoxyethylene caps. Polyols having both internal (random and / or blocked) oxyethylene moieties and outer oxyethylene blocked (capped) polyols are also useful. Higher alkylene oxides (ie, 1,2-butylene oxide or 2,2-butylene oxide)
Polyols of (3-butylene oxide), oxetane or tetrahydrofuran are also useful when used with the low unsaturated polyoxypropylene polyols of the present invention. Polyester polyols are also useful as accessory components in the practice of the present invention.

Preferred polyoxyalkylene polyether polyols are propylene glycol, dipropylene glycol, ethylene glycol, diethylene glycol,
Bifunctional and trifunctional polyols prepared by oxyalkylating bifunctional initiators such as 1,4-butanediol or trifunctional initiators such as glycerin and trimethylolpropane It is. These are non-limiting examples of initiators. Low unsaturation, ie, ASTM D-284
Measured according to 9-69 "Testing of urethane foam polyol raw material".
Polyols having a degree of unsaturation in the range of 012 meq / g to 0.020 meq / g are disclosed in U.S. Patent Nos. 5,158,922; 5,470,813;
82,908; and 5,545,601.

However, the most preferred polyols are ultra-low unsaturated, having an unsaturation level of less than about 0.010 meq / g, generally ranging from 0.003 meq / g to 0.007 meq / g. Is a reactive polyoxyalkylene polyol. Its synthesis is described in U.S. Patent Nos. 5,470,812, 5,482,908, and 5
No. 5,545,601 and 5,689,012.

Batch and continuous processes in which such catalysts are used are disclosed in co-pending US patent application Ser. No. 08 / 597,781 and US Pat. No. 5,689,012. Such polyoxyalkylene polyether polyols
Available commercially from the ARCO Chemical Company as ACCLAIM ^™ . The aforementioned patents are incorporated herein by reference.

[0013] Polymers that are also suitable for use in the foams of the present invention include polymer polyols. Polymer polyols are polyoxyalkylene polyols, polyester polyols, or other base polymers containing a finely dispersed solid polymer phase. Polymers having a solid phase resulting from the reaction of isocyanates with various reactive species can be used, including polyurethane urea dispersions ("PUD") and polyisocyanate dispersions ("PID"), For example, using solid phase polymers obtained from reaction with dialkanolamine and trialkanolamine ("PIPA polyol"), polymers having solid phase obtained from reaction with hydrazine ("PHD polyol"), etc. Can be. However, preferred polymer polyols include one or more vinyl monomers in situ in the presence of a suitable vinyl polymerization initiator.
Is a vinyl polymer polyol that can be prepared by polymerization with Preferred vinyl monomers include, but are not limited to, styrene, acrylonitrile, α-methylstyrene, methyl methacrylate, and the like. Most preferred are acrylonitrile and styrene, optionally with small amounts of other monomers. The solids content of the polymer polyol is from about 5 weight percent to about 70 weight percent, with a solids content ranging from 20 weight percent to 50 weight percent being preferred. Methods for preparing various polymer polyols are well known,
And numerous such polyols are commercially available. Most preferably,
The base polymer of the polymer polyol is a low or very low unsaturated polyoxyalkylene polyether polyol.

In addition to the polyol and the polymer polyol, the resin portion (B portion) preferably has at least about 50 equivalent percent of one or two based on the free isocyanate group content of the isocyanate portion (A portion). It contains the above low molecular weight chain extenders, preferably such chain extenders have a molecular weight of less than 300 Da, more preferably less than about 150 Da. Suitable chain extenders include ethylene glycol, diethylene glycol and triethylene glycol, propylene glycol, dipropylene glycol and tripropylene glycol, 1,3-propanediol, 1,4-butanediol, 2,2,4-trimethylpentane Diol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol,
Includes bifunctional species such as 1,6-hexanediol. Most preferred is 1,4-butanediol. Mixtures of chain extenders can be used.

[0015] The catalyst (s) are usually included in the resin portion of the formulation. Conventional urethane promoted catalysts such as various tin catalysts (ie, dibutyltin dilaurate, dibutyltin diacetate, tin octoate, etc.) are suitable. Amine-based catalysts such as diazabicyclooctane can also be used. If a preferred formulation containing substantially no water is used, the blowing catalyst required to promote the water-isocyanate reaction and to prepare a water-foamable microporous polyurethane / urea elastomer is required. And not. If the formulation contains a small amount of water, as described below, a blowing catalyst such as diazabicyclo [2.2.2] octane or another catalyst that catalyzes the isocyanate / water reaction may also be used in the formulation. Can be included. The catalyst type and amount can be readily selected by those skilled in the art of microporous polyurethane elastomers.

If the preferred composition according to the invention is substantially free of water, ie water is not intentionally added to the formulation to act as a blowing agent, the resin part is defined below. It can contain trace amounts of water as described. Polyurethane reactants often contain very small amounts of water, especially as the supplied polyols, chain extenders and crosslinkers. But the amount is so low that
If no noticeable foaming takes place and no reactive or non-reactive blowing agents or foaming agents are added, only non-porous polyurethanes are obtained from their use.

In the case of water-foamed microporous polyurethane / urea foams, the amount of water is from about 0.05 part to about 0.5 part water per 100 parts of the combined resin / isocyanate. Added in. Depending on these amounts, for example, a density of about 0.8 g / cm ³ to
Microporous foams in the range of about 0.2 g / cm ³ can be produced. In the present invention, preferred microporous foams, which are all polyurethanes, can be produced in this same density range without incorporating any water as a blowing agent. Such foams are substantially free of urea groups. However, if a small amount of urea groups can be tolerated for a particular application, a small amount of water can also be added. This "micro" amount of water can be defined as no more than 50 weight percent of the amount of water required to form the same density of microporous elastomer without foaming.

By way of example, 0.1 part water per 100 parts of the total elastomeric formulation results in a microporous elastomer having a target density of about 0.70 g / cm ^{3 in} the absence of foaming. In such a case, the "micro" amount of water in such a system is about 0.05
Part or less. The foaming results in additional microbubbles and / or larger microbubbles required to achieve the target density. Elastomers so produced have much less urea groups than microporous elastomers, all foamed with water, and therefore have significantly different physical properties, especially greater elongation and tear strength. It is expected to show Such elastomers in which the percentage of urea linkages is significantly less than that contained in a polyurethane / urea elastomer of similar density, all foamed with water, are termed as the term is used herein. Is still considered a polyurethane microporous elastomer and not a polyurethane / urea elastomer.

Although the isocyanate-reactive component is described as “Part B” or “Resin Part” above, this term means that the isocyanate-reactive component must be mixed into a single component. Should not be interpreted as such. While such an interpretation is certainly possible and may be preferred in some circumstances, when manufactured at high processing speeds, the various resin subcomponents can be combined with Henke, Kraus-
It can be delivered to multi-port mixing heads, such as mixing heads supplied by Maffei and other manufacturers. The combined feed stream of the resin portion can then be foamed and combined with the foam of portion A. Alternatively, Part A (isocyanate component, simultaneously or separately) can be added as a separate feed stream with the components of Part B and foamed.

The isocyanate component used to obtain the isocyanate-terminated prepolymer and the isocyanate-terminated quasi-prepolymer comprises organic aliphatic and aromatic diisocyanates and polyisocyanates useful in the preparation of polyurethane polymers. Can be selected. Non-limiting examples of suitable isocyanates are given below:
Aromatic isocyanates such as 2,4-toluene diisocyanate and 2,6-toluene diisocyanate and mixtures thereof; various methylene diphenylene diisocyanates (MDI), including 2,2'-MDI, 4'-MDI and 4
, 4'-MDI and mixtures thereof; modified aromas such as isocyanates prepared by reacting the isocyanate with itself or by reacting with reactive low molecular weight or oligomeric species Aliphatic isocyanates, especially carbodiimide-modified MDI, uretdione-modified and urethane-modified MDI; polymer MDI; and various aliphatic and cycloaliphatic isocyanates, such as 1,6-hexanediisocyanate, 1,8
-Octane diisocyanate, 2,4-methylcyclohexanediisocyanate and 2,6-methylcyclohexanediisocyanate, 2,2′-dicyclohexylmethane diisocyanate, 2,4′-dicyclohexylmethane diisocyanate and 4,4'-dicyclohexylmethane diisocyanate and the like. Modified aliphatic isocyanates and cycloaliphatic isocyanates are also useful.

The prepolymers preferably used are stoichiometric excess diisocyanates or polyisocyanates, together with higher functionality oxyalkylating species, polyoxyalkylene glycols or one or more. Isocyanate-terminated prepolymers prepared by reacting with a mixture of polyalkylene glycols. The average nominal functionality is preferably between about 2.0 and 2.2, most preferably about 2.0. Suitable glycols include polyoxypropylene glycols; polyoxypropylene glycols further containing up to about 30 weight percent of oxyethylene moieties as inner and / or outer blocks and / or as random internal oxyethylene moieties; Polytetramethylene ether glycol (PTMEG) is included. The polyoxyalkylene polyol component can contain small amounts of polyester diol, polycaprolactone diol, and similar species. The isocyanate-reactive component preferably has a molecular weight of about 1000 Da to about 15,000 Da, more preferably 1000 Da to 8000 Da, and most preferably about 2000 Da.
４4000 Da. Most preferred are very low unsaturated polyoxypropylene homopolymer glycols and very low unsaturated polyoxypropylene / polyoxyethylene copolymer glycols containing random internal oxyethylene moieties. This latter is preferably carried out, as described above, with DM
Prepared with C catalyst.

The isocyanate-terminated prepolymer desirably has an isocyanate group content of between about 2% and 18% by weight, preferably between 4% and 12% by weight. It is preferably between about 6 weight percent and 10 weight percent. Low viscosity isocyanates (eg, TDI and MDI) can further be used in the process according to the invention in which the individual components or the separate A and B parts are first mixed and then foamed. In this case, of course, the mixture of polyol, low viscosity isocyanate, chain extender and the like has a foamable viscosity such that a stable non-disintegrating foam can be obtained. However, it is generally necessary to use an isocyanate-terminated prepolymer for elastomers having the desired physical properties. In embodiments of the present invention where Part A and Part B are foamed separately, the isocyanate component of Part A must have its own foamable viscosity. For this reason, isocyanate-terminated prepolymers are particularly suitable, but foamable viscosity isocyanates can be obtained by adding viscosity modifiers to low viscosity diisocyanates or polyisocyanates, quasi-prepolymers or low viscosity prepolymers. It can be prepared by adding to a polymer.

[0023] Either the combined feed streams or the separate feed streams, foaming must generally occur in the presence of a suitable foaming surfactant. Such surfactants are available from OSI, Inc. Can be obtained from One such surfactant is VA
X6123 surfactant. Other surfactants may also be useful. Certain components or portions may be capable of foaming without the addition of foaming surfactants. The term "microporous and foamable" with respect to a complete system, system A or B part, or a component of the system, refers to a system or part or component which is suitable for forming a microporous elastomeric part with a density and a suitable density. It shows that it may be possible to foam into a cell size stable, non-disintegrating foam. Such "microporous and foamable" ingredients generally include one or more foaming surfactants.

The expanded microporous foam of the present invention has the physical properties as indicated by the overall density difference when compared to the microcellular elastomer foamed with water,
It was surprising that it showed little variation in core density. this is,
This is particularly unexpected given the tendency of conventional foamed foams (not microporous) to easily collapse. However, the most surprising thing is that the components of Part A and Part B are foamed separately, the foam is combined and molded into a fully cured microporous polyurethane with excellent physical properties. The fact was that an elastomer could be obtained.

In addition to the reactive components described above, the formulations can contain other conventional additives and auxiliary substances (eg, dyes, pigments, plasticizers, fillers, etc.). Such components are present in minute amounts and, if present, need not be considered when calculating or measuring the density of the microporous foam.

[0026] The foamed reactive formulation is introduced into a suitable mold and generally heated until the elastomer exhibits sufficient green strength to release from the mold. For example, the mold can be conventionally preheated to 50 ° C, and the foamable mixture is introduced and the mold is held in a 50 ° C dryer until cured. The foam is generally introduced into the mold under positive pressure. Positive pressure ensures that the cavity of the mold is completely filled and a gap-free part is obtained.

The term “permanent non-organic gas” is a gas under standard temperatures and pressures, and is not a hydrocarbon or halocarbon, but is incorporated as a gas that is not generated by a chemical reaction. Substance. Preferred permanent gases are nitrogen,
Air and carbon dioxide or mixtures thereof. The term should not be construed as requiring the complete absence of an organic blowing agent. Because small amounts of such blowing agents can be added without causing a substantial change in physical properties, and therefore do not depart from the spirit of the invention. The amount of organic blowing agent must be less than 20 weight percent of the calculated amount of blowing agent required to prepare a non-floss foamed foam of similar density to satisfy the above definition. Preferably, no organic blowing agent is used. A substantial part, preferably all, of the gas contained in the gas bubbles should be introduced by foaming and / or by the addition of small amounts of water. Preferably, at least 50% of such gas is air, nitrogen, carbon dioxide or a mixture thereof introduced by foaming,
It has or does not have non-condensable (0 ° C. or higher) water vapor. More preferably, the gas mixture comprises 70% of the total gas contained in the microbubbles, most preferably more than 90%.

Although the present invention has been described in general terms, further understanding is provided herein by way of illustration only and is not intended to be limiting, unless otherwise indicated. It can be obtained by referring to a specific embodiment.

Examples 1 and 2 Microporous elastomers were prepared according to the following procedure:

The formulations shown in Table 1 were foamed using a wire whip mixer. The obtained foam had a density of 0.67 g / cm ³ .

[0031]

[Table 1] Table 1

¹ Polyol A is a KOH-catalyzed glycerin-initiated polyoxypropylene triol, having a polyoxyethylene cap of 19% by weight and a hydroxyl number of 35. ² Polyol B is a polymer polyol based on Polyol A and nominally contains 40% by weight acrylonitrile / styrene solids.

[0033] Separately, a prepolymer composition prepared by pre-reacting the components shown in Table 1a was foamed using a wire whip mixer. The resulting prepolymer foam had the density shown in Table 1a.

[0034]

[Table 1a]

The foams of Table 1 and Table 1a were whisked together, poured into a 50 ° C. mold and allowed to cure.
The densities of the foams and elastomers and the physical properties of other elastomers are shown in Table 2 below.

[0036]

[Table 2] Table 2 ^{* A} small amount of water was taken into the sample due to room humidity. This resulted in a lower elastomer density than expected.

Comparative Example C1 A polyurethane / urea elastomer for comparison was foamed with water at a density of 0.4.
Prepared from a similar formulation except that it contained enough water to give 9 g / cm ³ (target density, 0.50 g / cm ³ ) of microporous elastomer.

One of the advantages of microporous elastomers that do not contain urea groups is improved tear strength. Tearing is one of the most important properties in footwear applications. The table below compares the tear properties of water-foamed (foamed) microporous elastomers and air-foamed (foamed) microporous elastomers.

[0039]

[Table 3] Table 3

As illustrated in Table 3, the microporous polyurethane elastomer prepared by foaming had a 46% improvement in split tear and an equivalent density of polyurethane / urea foam foamed with water. C showed a 30% improvement in tearing. The polymer polyol used in Part B of the formulations of Examples 1 and 2 contained a conventionally catalyzed polyoxypropylene / polyoxyethylene based polyol.

Example 3 A foam formulation was added to a mixing dish with 4,4'-MDI and a molecular weight of about 4000 Da.
48.61 g of 7% NCO prepolymer prepared from ultra low unsaturated polyoxypropylene / polyoxyethylene diol of 4,4'-MDI and about 600
121. Prepared from 0 Da ultra-low unsaturated polyoxypropylene triol
5 g of 7% NCO prepolymer; 42.4 g of butanediol; and 6.1 g
Of VAX6123 foaming surfactant.

The prepolymer prepared using the ultra-low unsaturated polyol was added to a mixing dish along with a chain extender and a foaming surfactant. These are mixed for 30 seconds before the catalyst (0.19 g of BL11, 0.16 g of NIAX® 33LV)
Was added and whipped for 60 seconds to continue mixing. The resulting foam was poured into an 8 ″ × 6 ″ × 1 ″ (20.3 cm × 15.2 cm × 2.5 cm) aluminum mold preheated to 50 ° C. and cured at 50 ° C. for 5-10 minutes.

Example 4 A formulation was made, foamed, molded and cured in the same manner as in Example 3, and using the same formulation. However, the initial mixing was reduced to 16 seconds and the mixing after catalyst addition was reduced to 30 seconds.

[0044]Comparative Examples C3 and C4 The elastomer was loaded at 0.53 g / cm for comparison.³And 0.56 g / cm ³ Water to prepare a water-blown microporous foam having an overall density of
Same arrangement as used in Examples 3 and 4, except that it was used as a blowing agent
The compound was prepared from Physical properties of foams and foams foamed with water
Is shown in Table 4 below.

[0045]

[Table 4] Table 4

From the table, it can be seen that the foam foam, which shows little difference between the overall density and the core density, has a greater consistency. further,
These foams had unexpectedly higher hardness and also higher tensile strength. Both C and split tears were significantly improved, with greater resilience and dramatically reduced compression set. In footwear applications, small compressive strains are very important.

The foam properties shown in the table reveal some significant differences between the foamed and water foamed samples. It is believed that these differences may be due to differences in hard segment composition. The foamed sample is 100% urethane, while the foamed sample with water is a mixture of urethane and urea.

In addition to the properties shown in the table above, compression hysteresis techniques that could correlate with shoe comfort factors were investigated. The test involves 5 repeated compressions at a known speed for 50% deformation of the sample. The table below shows the results obtained on the fifth cycle at three speeds of 5 inches / minute, 10 inches / minute and 20 inches / minute. The test materials are the same materials listed in the table above.

[0049]

[Table 5] Table 5 The foamed system exhibits superior hysteresis and greater load carrying capacity as compared to the system foamed with water.

Example 5 and Comparative Example C5 Microporous elastomers were prepared using two similar elastomer formulations and the physical properties of the elastomers were compared. The first elastomer was foamed. Water was added to the second formulation to produce a water / foamed polyurethane / urea microporous elastomer. Both samples contain 2500 g of Acclaim ^™ 42
01 (having a hydroxyl number of 2 available from ARCO Chemical Co.)
8 polyoxyalkylenediol) with 856.1 g of Mondur® M (pure MDI). Both samples also have 2
500 g of Acclaim ^™ 6300 (ARCO Chemical Co.
An ultra-low unsaturated triol-type isocyanate-terminated prepolymer prepared by reacting 858.1 g of Mondur® M with a hydroxyl number of 28, a polyoxyalkylene triol also available from ing. The formulations are shown in Table 6a below.

[0051]

Table 6a

The physical properties of the elastomer are shown in Table 6b below.

[0053]

[Table 6b]

Example 6 and Comparative Example C6 Two foamable formulations were prepared in the same manner as in Example 3, foamed and cured. The microporous polyurethane elastomer of Example 6 was prepared according to the procedure of Acclaim® 4200 polyether polyol, 4000 Da molecular weight and 0.005 m.
Prepared from polyoxypropylene diol with eq / g unsaturation. The microporous polyurethane elastomer of Comparative Example C6 was prepared from a polyoxypropylene diol having a molecular weight of 4000 Da, but having a higher degree of unsaturation (about 0.08 meq / g) in the conventional range. The results are shown in Table 7 below.

[0055]

[Table 7] Table 7

The term “unfilled density”, if a foam is used, means the density when the foam contains no filler. Molecular weight and equivalent weight are the number average molecular weight and number average equivalent weight in Daltons (Da). The term "primary" means 50% or more. The term "small amount" means less than 50%. These percentages are by weight unless otherwise indicated. Each component disclosed in the present specification can be used by excluding components that are not necessarily required for achieving the object of the present invention, and in particular, components not described in the present specification. And methods can be used with exclusion. The necessary components include isocyanate- and isocyanate-reactive components, whether present as isocyanate-reactive polyols or incorporated into isocyanate-terminated prepolymers or isocyanate-terminated quasi-prepolymers. At least one is prepared from a low or very low unsaturated polyol such that the latter comprises at least 35 weight percent (preferably a major portion of the total polyoxyalkylene polyol component of the formulation). .

Although the invention has been described in detail, many changes and modifications can be made to the invention without departing from the spirit or scope of the invention as set forth herein. It will be clear to those skilled in the art.

──────────────────────────────────────────────────続 き Continuation of front page (81) Designated country EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE ), OA (BF, BJ, CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, KE, LS, MW, SD, SL, SZ, UG, ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AE, AL, AM, AT, AU, AZ, BA, BB, BG, BR , BY, CA, CH, CN, CU, CZ, DE, DK, EE, ES, FI, GB, GD, GE, GH, GM, HR, HU, ID, IL, IN, IS , JP, KE, KG, KP, KR, KZ, LC, LK, LR, LS, LT, LU, LV, MD, MG, MK, MN, MW, MX, NO, NZ, PL, PT, RO, RU, SD, SE, SG, SI, SK, SL, TJ, TM, TR, TT, UA, UG, UZ, VN, YU, ZA, ZW (72) Inventor Nigel Barksby United States 25064 West Virginia Dunbar, Dogwood Rain No. 100 F term (reference) 4J034 BA08 CA04 CB03 CC03 CE01 DA01 DB03 DG02 DG03 DG04 HA06 HA07 HB06 HB09 HC03 HC12 HC17 HC22 KC17 KD02 KD11 NA01 QA02 QA03 QA05 QA07 QB01 RA03 RA10 RA12

Claims (25)

[Claims] 1. A gas under standard temperature and pressure; not a hydrocarbon or a halocarbon; and one or more substances directly incorporated as a gas and not formed in situ A microporous polyurethane elastomer filled with microbubbles, said elastomer comprising a stoichiometric excess of one or more diisocyanates or polyisocyanates, having an average equivalent weight of more than 1000 Da. A large polyoxyalkylene polyol component, and at least one polyoxyalkylene polyol composition having an average equivalent weight of at least 1000 Da and an average functionality of 2.0 or more; The molecular weight of at least 50 equivalent percent based on the reactive isocyanate groups is 3 Foaming at least one isocyanate-terminated polyoxyalkylene prepolymer prepared by reacting with an aliphatic glycol chain extender of less than 0 Da to prepare a curable foam, and then molding the foam into a mold Introducing a polyoxyalkylene polyol obtained by curing the foam and having a degree of unsaturation of less than 0.015 meq / g, the combined polyoxyalkylene polyol component and the polyoxyalkylene polyol A microporous polyurethane elastomer that is at least 35 weight percent of the total polyoxyalkylene polyol in the composition. 2. Foaming all or a portion of the isocyanate-reactive component to a first foam, and foaming a composition containing an isocyanate-terminated prepolymer to a second foam, wherein said foam comprises a second foam. The elastomer of claim 1, wherein the first and second foams are combined to provide the curable foam. 3. An elastomer according to claim 1, wherein all the reactive components are mixed vigorously and foamed together to obtain the curable foam. 4. The isocyanate-terminated prepolymer has an average functionality of 2 to 4.
4. One or more microbubble-foamable isocyanate-terminated prepolymers prepared from one or more polyoxyalkylene polyethers of Claim 4. An elastomer according to claim 1. 5. The at least one isocyanate-terminated prepolymer comprises:
A stoichiometric excess of one or more diisocyanates or polyisocyanates is combined with one or more low unsaturated polyoxypropylene polyols having an unsaturation of less than 0.010 meq / g. The elastomer according to any one of claims 1 to 4, which is a prepolymer prepared by reacting. 6. The elastomer of claim 5, wherein said polyoxypropylene polyol contains an oxyethylene moiety in an amount up to 30 weight percent. 7. The elastomer of claim 6, wherein said oxyethylene moiety is a random internal oxyethylene moiety. 8. A urea group is present on said polyurethane microporous elastomer,
The urea groups are formed by the reaction of free isocyanate groups with water added as an auxiliary blowing agent, the amount of water being required to produce the same density foam without foaming. The elastomer according to any one of claims 1 to 7, which is 50% by weight or less. 9. An elastomer according to claim 1, wherein the one or more substances consist essentially of one or more of nitrogen, air and carbon dioxide. 10. The density of the microporous elastomer is 0.2 g / cm ^{3 to} 0.1 g / cm ³ .
8 g / cm ^3, and preferably elastomer according to any one of claims 1 to 9 is ^{0.25g / cm 3 ~0.5g / cm 3} . 11. The elastomer according to claim 1, which has substantially no urea bond formed by a water / isocyanate reaction. 12. The main proportion of the total polyoxyalkylene polyol is between 0.
The elastomer according to any one of claims 1 to 11, comprising one or more polyoxypropylene polyols having an unsaturation degree of less than 015 meq / g. 13. The main proportion of the total polyoxyalkylene polyol is from 0.
The elastomer according to any one of claims 1 to 12, comprising one or more polyoxypropylene polyols having an unsaturation degree of less than 010 meq / g. 14. The elastomer according to claim 1, wherein all polyoxyalkylene polyols having an equivalent weight greater than 1000 Da have an unsaturation of less than 0.015 meq / g. 15. A process for preparing a microporous polyurethane elastomer, comprising: a) one or more polyoxyalkylene polyols together with one or more substances as defined in claim 1 or 9. Foaming a first foamable mixture comprising one or more isocyanate-reactive components comprising: b) obtaining a first foam; b) according to claim 1 or 9. A second foamable mixture containing one or more substances, together with one or more isocyanate-terminated prepolymers having an average isocyanate group content of 2% to 18% by weight To obtain a second foam, wherein the isocyanate-terminated prepolymer comprises a stoichiometric excess of one or more diisocyanates Is prepared over bets or polyisocyanates by reaction with the polyoxyalkylene polyol component, the total polyoxyalkylene polyol in the combined has been the isocyanate-reactive component and the isocyanate-terminated prepolymers, 2
At least 35 weight percent of one or more low unsaturated polyols having a functionality of 8, an equivalent weight of 1000 Da or more, and a degree of unsaturation of less than 0.015 meq / g; c) Combining the one foam and the second foam to obtain a curable foam; d) introducing the curable foam into a mold to cure the curable foam; e). Removing the microporous polyurethane elastomer from the mold. 16. The first foamable mixture comprises one or more aliphatic chain extenders having a molecular weight of at least 50 equivalent percent, based on the amount of free isocyanate used in the process, of less than about 300 Da. The method of claim 15, further comprising: 17. The method according to claim 15, wherein the low-unsaturation polyol has an average degree of unsaturation of less than 0.010 meq / g. 18. The method according to claim 15, wherein the isocyanate-reactive component has an average degree of unsaturation of less than 0.010 meq / g. 19. A method for preparing a microporous polyurethane elastomer having a low urea group content, comprising: a) one or more isocyanate-terminated prepolymers or isocyanate-terminated quasi-prepolymers as an isocyanate component; Selecting an isocyanate component consisting essentially of a polymer, wherein said isocyanate-terminated prepolymer or isocyanate-terminated quasi-prepolymer comprises a stoichiometric excess of one or more diisocyanates Or prepared by reacting a polyisocyanate with a polyol component, said polyol component having, in a major part, a functionality of 2-8, an equivalent weight of 1000 Da or more, and an unsaturation of less than 0.015 meq / g. Consisting of one or more low unsaturated polyols having One or more polyoxyalkylene polyols having a nominal functionality of at least 50 equivalent percent based on the reactive isocyanate groups of component (a), and one or more glycols having a molecular weight of less than 300 Da Selecting the isocyanate-reactive component comprising a chain extender such that the average nominal functionality of component (b) is from 2 to 2.3, wherein said isocyanate-reactive component is a single component C) said component (a) by combining one or more substances as defined in claim 1 or 9 with component (a) and component (b). And component (b) as 9
Foaming with an isocyanate index of 0 to 110 to obtain a stable curable foam; d) introducing the curable foam into a mold; and e) curing the foam to produce a microporous foam. Obtaining a polyurethane elastomer. 20. The method according to claim 19, wherein the foaming is performed in the presence of a sufficient amount of one or more foam stabilizing surfactants. 21. Component (b) further comprises a small amount of water, said small amount of water forming without foaming a microporous elastomer having the same density of non-permanent gas foamed elastomer. 21. A process according to claim 19 or claim 20, wherein the amount of water is less than 50% by weight. 22. The isocyanate component consists essentially of one or more isocyanate-terminated prepolymers, and each of the prepolymers comprises one or more MDIs, modified MDIs or mixtures thereof. Prepared by reacting with at least one low-unsaturated polyoxypropylene polyol, wherein the polyoxypropylene polyol contains no more than 30 weight percent oxyethylene moieties, and the polyoxypropylene polyol has a number average molecular weight of 1000 Da to 1000 Da.
2. The composition of claim 1, wherein the average unsaturation is less than 0.015 meq / g.
22. The method according to any of 9 to 21. 23. The method of claim 22, wherein said average degree of unsaturation is less than 0.010 meq / g. 24. One or more polyoxypropylene polyols in which the main proportion of the total polyoxyalkylene polyol has an unsaturation of less than 0.15 meq / g, preferably less than 0.010 meq / g Claim 15 consisting of
18. The method according to any one of claims 17 to 17. 25. The process according to claim 15, wherein all polyoxyalkylene polyols having an equivalent weight of more than 1000 Da have an unsaturation degree of less than 0.015 meq / g.